There is a strong tradition of women giving chocolates to men on Valentines Day. There are two types of chocolates, “Giri-choco” (obligation chocolate), and “Honmei-choco”.
Giri-choco is meant to be for friends, colleagues, bosses, and close male friends. “Giri” means obligation hence this Giri-choco has no romance involved.
On the other hand, Honmei-choco is given to a boyfriend, lover, or husband with true love. Japanese women often prepare the Honmei-choco by themselves as many of them think it is not true love if they just buy the ready made chocolate at shops.
You will start seeing large displays of chocolate, often heart-shaped in department stores and grocery stores from mid-January. Days before the Valentine’s Day, stores get packed with a large variety of chocolates, the cooking tools, and women!
The White day is celebrated in the 14th of Mars, it's very similar to Valentines Day but in this case men thank the women who gave them chocolates giving them a gift.
The origin of this festivity was on 1965 when a marshmallow seller told to men that they should give something in return to women for the chocolates they received the last month
Meanings... Marshmallows(マシュマロ)~ “I am sorry, I am not interested in you!” Giving out marshmallows for White Day is considered “no interest” for the person.
Candies(キャンデー)~ “I love you too!” Guys pick candies as a gift to return to someone they love. Candies seem to be the one that shows the true love to a special woman.